Low-dimensional nonlinear control of nonisothermal plug-flow reactors

A low-dimensional nonlinear feedback control scheme for a nonlinear partial differential equation (PDE) system is addressed. The main design procedure involves the use of a feasible approximation method to establish a finite-dimensional and interconnected nonlinear dynamics, and then utilize the cascaded nonlinear feedback design for achieving uniform output regulation. When the new steady state of closed-loop system can be planed, the steady-state input distribution can be produced such that the lowest possible number and positions of actuators can be determined. With the aid of the nonlinear inverse design procedure, the low-dimensional nonlinear controller is proposed and ensures the bounded output regulation. In the illustrative example, this approximate feedback design is shown to be robust and effective in controlling a nonisothermal tubular reactor at possibly realistic situations.